Smelting process and apparatus.



E.A.MATHERSL SMELTING PROCESS AND.APPARATUS.

APPLICATION FILED DEC, 20. 191 1- 1,242,833@ Patented Oct, 9,1917,

- 3 SHETS-SHET l- INVENTQR v4. m r

ATTORNEY v E. A. MATHERS. SMELTING PROCESS AND APPARATUS.

APPLICATION FILED DEC. 20. 1911.

Patented Oct. 9,1917.

' 3 SHEETS-SHEET 2.

WITNESSES Y E. A. MATHERS.

SMELTING PROCESS AND APPARATUS. APPLICATION FILED DEC. 20, I911.

Patented A Oct. 9, 1917.

3 SHEETS-SHEET 3- IIIIIII/I.IVIIIIIIIIIIIIIIIIIIIIIIIAkll .36" ,INVENTORv ATTORNEY I New York,

UNITED STATES EZRA A. MATHERS,

OF NEVI YORK, N. Y.

SMELTENG- PROCESS AND AEPARATUS.

Application filed December 20, 1912.

, new and useful Improvements in Smelting Processes and Apparatus, ofwhich the following is a specification.

My invention relates to a process of and apparatus for electricallytreating ores, e. 9., electric smelting.

The objects of the invention are to provide means for facilitating therapid and cheap treatment of highly refractory ores, for treating thematerial in a substantially continuous operation, thereby reducing thecost of treatment and obtaining a greater productive capacity ofapparatus, to provide means whereby the gases resulting from thecombustion and smelting after purifying are returned to the smelter andutilized therein in a continuous cycle, and to provide means wherebysaid gaseous products may be revivified by the addition of air, for thepurpose of enabing such gaseous products to be re-utilized in thefurnace. v

With these ends and others in view my invention consists of theapparatus hereinafter described and claimed.

In the accompanying drawings Figure 1 is a vertical section of apreferred form of apparatus inaccordance with. my invention, Fig. 2 adetail cross section at right angles to Fig. 1, of the regulablecontrolling gate for the ore hopper,

Fig. 3 an end elevation of the apparatus partly in section,

Fig. 4 a cross section on the line mm of Fig. 1, I

Fig. 5 a detail side elevation showing the electrode adjusting means,

Fig. 6 a longitudinal section of one of the electrode carrying members.

Fig. 7 a detail side elevation of mechanism for resetting one of theelectrodes in arcing position. and

Fig. 8 a. detail cross section at right angles to Fig. 7.

In carrying out my process the ore or other material to be smelted isfirst preferably pulverized. by suitable crushing means, not shown, andis then introduced into a suitable hopper from which it is fed bygravity into the furnace in a quantity and at a' rate controlled by asuitable gate, or similar means, thespeed of operation of which maySpecification of Letters Patent.

tact with and through the stream of de-' scending ore in a manner toobtain the greatest surface contact therewith and thus fully utilize theheat of the arcs. During this treating with the arcs, the air introducedthrough the twyers (to be later described), as well as the other air inthe furnace, will act upon the ore to perform oxidationcf sulfur, etc.,as is well understoodin electric smelting. The resulting productsaccumulate in the bottom of the furnace and are there maintained in aheated state by suitable electric resistance means in order to maintainthe same ina fluent condition and the fused mass and slag are then ledtherefrom through tion or further treatment. The process is a closedfurnace method operating under pressure and to this end and also inorder to supply oxygen for oxidation of oxidizable constituents of theore, air under pressure may be admitted adjacent to each arc but in sucha manner as not to destroy the formation and desired direction ofprojection of said arcs. Instead of operating under air pressure it maybe found desirable in some cases to operate in a partial vacuum, inwhich instance only sufficient oxygen will be supplied for carrying outthe smelting reactions. in this modification, a vacuum pump will besubstituted for the gas washer, and the oxygen will be admitted asdescribed below.

The fumes and the gaseous products of combustion resulting from thesmelting operation are prevented from escaping and are carried out ofthe furnace and, after the ad dition of air thereto. are againintroduced into the furnace for the purpose of again subjecting the oreto treatment therewith while the surplus gases in excess of thosethatmay be utilized merely by the addition of air thereto are permittedto accumulate in a suitable chamber until of sufficient volume andpressure to be forced out through separate openings for utiliZaandserving to permit the drivi ng able washer, such as a trap containingwater, by which the absorbable impurities may be collected and drawn offand this washer also preferably communicates with a suitablewater-jacketed container, after which the again enter the furnace by asuitable flue leading to the lower part thereof. The flaming arereferred to herein is disclosed in my United States Patent No. 1,002,721and dated September 5, 1911.

Referring to the drawings, 1 is the smelting chamber of the furnacestructure proper which is built of suitable material provided with arefractory lining. This chamber has opposite sloping walls preferablyinclined at an angle approximating 60 degrees to the horizontal and oneof said walls 2 constitutes an inclined ore way for the pulverized orewhich may be fed into the furnace at the upper end of the chamber. Theopposite wall of the chamber is preferably 1n substantial parallelismwith the ore way 1 for the purpose of properly guiding and directing thegases and fumes resulting from the smelting operation. The inclined oreway 2 is provided with a series of steps 4. These steps have their uppersurfaces 5 also inclined downwardly from the surface of the are way andthe risers 6 of these steps meet the outer ends of the upper surfaces atan acute angle. The steps are spaced from one another for a sufiicientdistance to permit the pulverized stream of ore to be thoroughlydisintegrated by the heat and chemical action, as the ore falls from onestep to another and to permit the projection of the flaming arcs againstand through the flowing body of ore, from the surface of the ore waybetween the steps.

The pulverized ore is fed upon the upper step from the chute 7 of afeeding hopper 8 within which chute at the lowercnd thereof is mounted arotatable feed controlling gate 9 consisting of a longitudinally groovedwheel and acting in conjunction with the body of pulverized ore abovethe wall in the hopper to keep the opening of the hopper sealed againstthe upward escape of gases or fumes feed of the ore from the hopper onlywhen and so fast as the gate is turned by suitable means outside of .thefurnace, The gate 9 is mounted on a shaft 10 i ournaled in the walls ofthe ho per and carrying at its outer end a suitable rive wheelconsisting either of a pulley or a gear which may be connected to anysuitable mechanism capable of being regulated by an operator for thepurpose of chan the speed of the shaft and the consequent rapidity offeeding movement of the gate whereby the rate of feed of the ore to thefurnace may be regulated.

Adapted to project through the wall 2 of the smeltingbhainberaboveeachstep 3 is a negative electrode 1'1 of a pairof re pro ducing electrodes.This negative electrode is adapted to be fed by suitable manuallycontrolled operating means as the same is consumed and is also adaptedto be adjusted axially to present new surfaces to the complementaryelectrode. The complementary positive electrode 12 is also adapted toproject through the wall of the ore way and is adapted to extendsubstantially flush with the inner inclined surface of such ore way,theaction of each pair of electrodes being to project a flaming and pearshaped are into the interior of the smelting chamber. The positiveelectrode 12 is electrically connected with auxiliary electrode members13 projecting through the upper surface of each step and adapted toattract and draw downwardly into approximate parallelism with thedownwardly inclined direction of the ore way, the are produced by thenegative and positive electrodes, thereby drawing against and confiningto the body of ore the flaming arc and obtaining to the full theutilization of the heat units.

Each negative electrode is clamped within a suitable supporting sleeve141 mounted in the wall of the smelting chamber and provided at itsouter end with a suitable hand wheel 15 whereby the electrode may be fedinwardly by hand as same is consumed in the action of the furnace. Eachsleeve is also provided with'asuitable helicon gear 16 adapted to meshwith a similar gear 17 carried by a common shaft 18 extendingsubstantially parallel to the inclined outer sur' face of the ore wayand journaled in a suit able support 19 fixed to the furnace wall. Suchshaft is provided with a crank handle 20 at the upper end thereof forthe purpose of enabling the shaft to be rotated by hand whereby (ll ofthe negative electrodes may be rotated on their longitudinal axes so asto present new surfaces relative to the opposing positive electrodes.Each main positive electrode is also provided. with a hand feed wheel21, on supporting sleeve 22 in the inner'end of which is mounted anelectrode clamp 23. The sleeve 22 is made hollow and is adapted toreceive the flexible tube 24 through which air is conducted from asuitable source of compressed air. The inner end of the tube 24terminates in a diaphragm chamber25 within which is mounted a smalldiaphragm 26 having fixed thereto a stem 27 the upper end of which isadapted to contact with a pivotal. contact finger 27 of electricalconducting material. The above arrangement is adapted to be employedtoreestablish the arcing space between the electrodes when the circuit hasbecome dead from any reason. The contact finger suitablyconnectedelectrically with the main positive electrode and if for some 1 reasonthe current s not working properly in the electrodes so at no arc isbeing proreac es dnced compressed air is directed through the tube 24thereby raising the diaphragm and throwing the electric contact fingerinto contact with the negative electrode which establishes a circuitthrough the electrodes and contact finger and reestablishes the sparkingaction between the electrodes.

On each side of each negative electrode of each pair is an inlet 28 forair or other gas located slightly above the plane of the electrode so asnotto interfere with the projection of the arc thereof and also hav ingthe inlet so formed as to direct the current of air or other gasupwardly for the same purpose. These inlets are preferably incommunication with a source of compressed air outside the furnace, notshown, and they serve to supply the oxygen necessary for the oxidationof the ore and also to produce a forced draft throughout the furnace andits connected parts for the purpose of establishing a circulation of thegaseous products of combustion. and fumes. The radial flues constitutingthe air inlet means are respectively in communication with the oppositeends of a vertical circumferential flue 29 formed in the wall of thefurnace chamber and extending around said chamber from one air inletflue to the other, circumferentially and from near the bottom of thechamber to the upper end thereof, vertically. This flue 29-constitutespart of circulation system and adapted to comnaunicate with the same areoutlet means 30 consisting of short passages formed in the wall of thechamber substantially opposite to the respective air jet openings in theinclined ore way which outlet means permit the escape of the fumes andgaseous products of the smelting from the chamber into the vertical andcircumferential flue. The air inlet means 28 acting as an injector uponthe gases within-the fine 29 and thus draw said gases from the chamberthrough the fine and back into the chamber again with the additionthereto of fresh air under pressure thus utilizing the gases again inthe process of combustion and serving to more effectually burn oflcombustible matter in the ore.

- The pulverized ore as it passes downfrom the upper end of the chamberover the stepped and inclined oreway is brought into successive contactwith the separated and downwardly inclined fiamingelectric arcs. The oreuponits first contact with the ore way is roasted and then as it travelsalong said way is rapidly and effectively smelted in the successivearcs, the steps serving to break up the stream and afford more intimatecontact of the arcs therewith. The mixture of molten matter and slag,producedby the smelting operation, then descends and collects in thesettling basin 31 when it is maintained in its molten. condi'-' tion bymans of electric resistancemembers projecting into the bottom of thesettling basin. From the settling basin the matter and slag-are drawnoff through their respective openings 32 and 3'3.

The fumes and other gaseous products from the circumferential flue 29 inexcess of those consumed in the furnace will pass through branch. pipesSi leading from the top of said flue around the chute of the feedinghopper into an accumulator chamber provided with a refractory lining.This chamber communicates with a water trap system 36 comprising anupper pipe 37 and a lower settling pipe 38. The gases are drawn throughthe water in the upper pipe and any foreign impurities carried by thegases will be collected therein. The gases thus washed are then drawnthrough a suit able container 39 further washing the gases, and thusrevivifying the gases and enabling them to be employed again in theprocess. This container is surrounded by a water jacket 40 and from thecontainer a return pipe 41 is adapted to conduct the revivified gasesback to an entrance 42 leading into the lower part of the furnace.Joining this return pipe at its entrance into the furnace is asuitableair pipe 43 adapted to admit air to the furnace with the returned gases.At the upper end of the cylinder 40 there is an escape openingcontrolled by a suitable valve 44 whereby when the pressure of the gasespasses a predetermined point they will be permitted to escape to theatmosphere to relieve suchv pressure.

The process, as above described, may be employed in the smelting ofhighly refractory sulfid ores, but I do not limit myself to thetreatment of such ores.

It is clear that changes in the details of the steps of the process andof the features of construction of the apparatus may be madewithoutdeparting from the principle of the invention. The term ore asused in the specification and claims will be un derstood to include anymaterial which the apparatus may be found adapted to operate upon.

Having thus described my invention, what if claim is:

1. The process of smelting ores which consists in feeding asubstantially continuous stream of ore against a series of separatedheating bodies and projecting the heat of said. bodies downwardly in aline approximatingparallelism with the flow of ore. substantially as setforth.

Y 2. The process of smelting ores which consists in feeding asubstantially continuous stream of pulverized ore against a series ofseparated heating bodies and projecting the heat of said bodiesdownwardly. in a line approximating parallelism with the flow of ore,substantially as set forth.

e process of smelting ores which consists in feeding the same by gravityagainst an interru ilting and distributing surface and projectin saidstream rn )lZlO'll of forth.

l. The process of smelting ores which consists in pulverizing the oreand feeding the same by gravity against an interrupting and distributingsurface and projecting bodies of heating medium into said stream of oreat the points of interruption of the flow, substantially as set forth.

5. The process of smelting ores which consists in introducing the oreinto a closed electric furnace, forcing air under pressure into saidfurnace and maintaining a constant circulation throughout said closedfurnace and the parts communicating therewith of the air and gaseousproducts of combustion, substantially as set forth.

6. The process of smelting ores which consists in introducing the oreinto a closed electric furnace and subjecting said ore to the action offlaming-electric arcs, introducing air under pressure to said chambersand leading the gaseous products of combustion from said chambers andthrough a purifying agent and back to the furnace in a continuous cycle,substantially as set forth.

7. The process of smelting ores which consists in introducing the ore ina pulverized state into a closed electric furnace and sub jecting saidore to the action of fi aming bodies of heating medium into of ore atthe points of lnterthe flow, substantially as set electric arcs,introducing air under pres-' sure to said chambers and leading thegaseous products of combustion from said chambers and through apurifying agent and back to the furnace in a continuous cycle,substantially as set forth.

8. The process of smelting ores which consists in introducing the oreinto an electric furnace closed against escape of the prodnets ofcombustion to the atmosphere, introducing air under pressure to saidfurnace, leading the gaseous products of combustion the combustionchamber to a point of re-commingling with freshly admitted air andleading the excess gaseous-products of combustion through a suitablewasher and returning such gases to the combustion chamber, substantiallyas set forth.

9. The process of smelting ores which consists of introducing the oresby means of ric arcs in a furnace apparatus closed against escape of thefumes or gaseous products to the atmosphere and comprising the feedingof the ore in a substantially continuous stream co-flaming electricarcs, in-

troducing air under pressure to the combustion chamber of saidapparatus, leading the gaseous products of combustion in a continuouscycle from raid combustion chamber and back thereto, introducing inconjunction with the return gases a continuous supply of fresh air,leading the accumusaid feed way at intervals and electric arcproducingmeans mounted between said members, substantially as set forth.

11. A smelting furnace comprising an inclined ore way leading downwardlyfrom the upper end of the furnace chamber, members projecting from thesurface of said ore way and each having downwardly inclined uppersurface at an angle to the ore way surface and a lower inc l surface,said members beingspaccd apart tically and heating means between theadjoining members, substantially as set forth.

12, In a smelting furnace, comprising an inclined gravity feed ore waytherein, step members projecting from the surface of said ore way, anelectrode between adjacent step members, and a complementary electrode,substantially as set forth.

13. In a smelting furnace, the combination with means providing asmelting chamber, means to feed material to the upper end of saidchamber, a downwardly extending inclined ore way in said chamber havingopenings therethrough, and electric are producing means in a planeinclined downwardly from the surface of said ore way and operable toproject an are against the ore passing over said ore way, substantiallyas set forth.

14. In a smelting furnace, the combination with means providing asmelting chamber, an inclined ore way in said chamber, inclined stepsprojecting electrodes mounted in openings in said ore way, and meansoperable to draw said arcs downwardly, substantially as set forth.

15. In a smelting furnace, the combination with means providing asmelting chamber, of means for feeding ore by gravity over a. surface insaid chamber, an electric arc electrode projecting into said chamber andoperable to produce an are acting against the ore passing over saidsurface, means outside the chamber for feeding said electrode and meansfor adjusting the same circumferentially to present new surfaces, andcomplementary electrode means, substantially as set forth.

16. In a smelting furnace, the combination with means providing asmelting chamber of a series of pairs of electrodes for producing arcsin said chamber, and means opmesses i erable outside the chamber forsimultaneously adjusting one'electrode of each pair to present newsurfaces to the opposing electrodes.

11'. In a sm lting furnace, the combination with means providing asu'ielting chainber of a series of pairs of are producing electrodes,means for rotating simultaneously the corresponding electrodes of allthe pairs and individual means for feeding said electrodeslongitudinally.

18. In a smelting furnace, the combination with a smelting chamber,means to close the furnace against the escape of gaseous products ofsmelting, heating means 'ithin the chamber, means to admit air underpressure to said chamber, gas purifying means, and means to provide acontinuous circulation of gaseous products from said chamber tl'nfoughthe purifying means and back to the chamber, substantially as set forth.

19. In a smelting furnace, the combination with a chamber of downwardlydirected heat bodies and adjacent compressed air admitting meansdirected across the direction of the heat bodies, substantially as setforth.

20. In a smelting furnace, the combination with a chamber, of flamingelectric are means in said chamber, means to admit compressed air tosaid chamber adjacent to said arcs, outlet means for gaseous matterleading from said chamber opposite. said air inlets and a circulationflue leading from said outlet means back to the furnace andcommunicating With the air inlets, substantially as set forth.

21. In a smelting furnace, the combination With a chamber, smeltingmeans thercin, a source of compressed air, air inlet means insaidchamber, gas outlet means from said chamber, gas Washing means com--municating with said outlet means and means of return communicationbetween said Washing means and the furnace chamber, substantially as setforth.

22. A smelting furnace comprising a chamber, downwardly directed heatbodies therein, and adjacent fuel supplying means, substantially as setforth.

23. A smelting furnace comprising a chamber, means for supplying heatbodies therein, and means for supplying fuel, said sets of means beingarranged to project the heat bodies and fuel to intersect, substantiallya:

with said chamber, a gas accumulator, a gas washer. fuel adding means incommunica-' tion with said washer and means of communication betweensaid means and the smelting chamber, "substantially as set forth.

26. In a smelting furnace, the combination with :1 smelting chamber,means to feed pulyerized ore in a substantially continuous stream tosaid chamber, means to prevent the escape of the gaseous products fromsaid furnace, a water trap device communicating with the it'uri'iacechamber, at two points, to

establish a circulation and a source of air llillltl pressurecommunicating with said chamber, substantially as set forth 2?. incombination with a smelting furnace in uns for producii'ig a completecycle of circulation of gaseous products from the furnace and backagain, a Washer interposed in said circulation means, and a fuel compound. container also interposed in said circulation means,substantially as set forth.

28. In a smelting furnace, the combination 'with a smelting chamber sti:ture, of ilan'iiug electric are means in the chamber, a source of airunder pressure communicating with said chamber, means to revivifygaseous products of combustion, and to lead said products in acontinuous cycle f'om the chamber through said revivifying means andback to the chamber, substantially as set forth.

In Witness ,whereof, I have hereunto set my hand and seal atPhiladelphia, Penna. this fourteenth day of December, A. D. nineteenhundred and eleven.

EZRA A. MATHERS. l/Vitnesses E. N. BRADFORD, S. C. MTLLWARD.

Copies of this patent may be obtained for five cents each, by addressingthe commissioner of Patents,

' Y Washington, D. G.

